Well I'm looking into getting a 18" SA lungfish and 2 16" clown knifes to put with my silver aro and my gar. Wanted your guys expert opinion if it would work before i spend the money. Its funny because Ive wanted all these fish together since the first time I heard of them but then I realized they were all ancient fish and that made it even cooler. They would all be living in a 140g tank. Lemme know if u think it'll work out plz. Also is it true that any current will kill lungs? I was gunna run 2 Fluval 404's cause i got them already, would that work?